The applicability of the mid-range infrared spectroscopy method to establish the quality indicators of compound feed

Abstract

The purpose of the research is to study the functional capabilities of medium–wave infrared spectroscopy to determine the quality indicators of concentrated compound feed. The study investigated the nutrient content (the total number of amino acids and carbohydrates) by reflective infrared spectroscopy in 4-component compound feed and compared with the results of chemical analysis performed by arbitration methods. The optical properties were investigated and a comparative analysis of all 4 components of the feed was carried out (ground corn grain, beet pulp, corn bard, rapeseed meal). For the first time, spectral absorption characteristics of compound feed and its components in the mid-infrared area were obtained and a representative range for determining quality indicators was revealed. The infrared spectra were obtained using a MICRAN-3 microscope connected to the SIMEX FT-801 infrared Fourier spectrometer using the Savitsky-Goley algorithm. It has been established that the spectral absorption characteristics of α(k) have a maximum range of 710–1275 cm-1 for all feed components. The maximum tself is at 1060–1090 cm-1. The characteristics are qualitatively similar, but the largest reflection in the maximum area is characteristic of ground corn, and the smallest is for rapeseed meal. Integral reflection parameters were obtained in the absorption areas of proteins, fats and carbohydrates with an error of no more than 7.2 %. Beet pulp absorbs more than other components in the range of 800–1170 cm-1. For corn bard and ground corn, the absorption is approximately the same for each range. In the areas of protein absorption, the value of the absorption coefficient is significantly lower and the difference in absolute values is less noticeable. It is assumed that the reflection of the α(k) characteristic in the maximum area is most dependent on the carbohydrate content in the studied components.

Keywords

• compound feed components
• non-destructive testing methods
• optical radiation